1.School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, Hunan, China; 2.Guangxi Beibu Gulf New Material Co., Ltd., Beihai 536000, Guangxi, China
Abstract:Abstract: In order to reduce heavy metal pollution and nickel resources waste by the accumulation of low grade nickelcontaining waste lump ore, and at the same time achieve the effective utilization of solid waste and improvement of sintering performance of limonitic laterite, based on the characterization of the used waste lump ore and limonitic laterite, sinter indiators of limonitic laterite with different sintering processes were studied and the corresponding mechanism was revealed. The results indicate that, compared with sintering processes without hearth layer or with product sinter as hearth layer, sintering process using waste lump ore as hearth layer possesses better sintering performance with tumble index increased by 10.16% and 3.82%, productivity increased by 13.40% and 6.80%, and solid fuel rate lowered by 9.64% and 9.20%, respectively. Meanwhile, excellent metallurgical properties are obtained, i.e. RI of 78.24% and RDI+3.15mm of 96.79%. The investigation of consolidation mechanism demonstrates that, in the sintering process with waste lump ore as hearth layer, sintered ore mainly possesses large size and round pores with thick wall rather than large irregular thinwall pores and the area fraction of SFCA is increased from 7.27% and 8.78% to 12.21% with extending along the edge of the pores to the internal structure of sintered ore. Besides, the main solid phase, i.e. hercynite, is more effectively wetted by the liquid phases including SFCA and eutectic spineltype olivine phases with the grain aggregation and growth. All of them promotes the formation of closeknit sinter microstructure, leading to a higher sinter strength. Furthermore, waste lump ore with higher strength as hearth layer plays a better role on improving the permeability of sinter bed compared with product sinter of limonitic laterite which is beneficial to fully burning of anthracite, contributing to the substantial improvement of solid fuel rate and productivity of product sinter.
朱德庆1,薛钰霄1,潘建1,田宏宇1,潘料庭1,2,黄庆周2. 废弃块矿作铺底料强化红土矿烧结工艺及机制[J]. 钢铁研究学报, 2020, 32(7): 591-600.
ZHU De-qing,XUE Yu-xiao,PAN Jian,TIAN Hong-yu,PAN Liao-ting,HUANG Qing-zhou. Sintering performance and mechanism of limonite laterite strengthened by using waste lump ore as hearth layer. JOURNAL OF IRON AND STEEL RESEARCH , 2020, 32(7): 591-600.